Camshafts are used in internal combustion engines for controlling the intake and exhaust valves and, for this purpose, have cams which, via a valve drive, more specifically, via a rocker arm, actuate an associated intake or exhaust valve. Said rocker arms are mounted so as to be pivotable about a rocker arm shaft and are arranged, for example, on a cylinder head. The camshaft itself is also mounted on the cylinder head, for example in split bearing shells, one of which is arranged on the cylinder head and the other one is formed by a bearing block. In general, such a valve drive is constructionally complicated and therefore relatively expensive.